Please! Really need some help with this chemistry?

[calleighismygirl]

If the density of gold is 19.3 g/cm^3, then what is the volume(in cubic centimeters) of a sample of gold with mass 0.715 kg?
If this gold sample is shaped like a cube, how long is each edge in centimeters?

[kumorifox]

Density = mass/volume, so volume = mass/density.

Just make sure the units match, i.e. convert the mass of gold to g. To get the length of the cube edge, take the cube root of the answer.

[david_bowman_sc]

First, try to get the units the same for all the factors in the problem.
So, since the density is g/cm^3, convert the mass of the gold to grams. 0.715kg is converted to grams by multiplying by 1000. So 0.715kg becomes 715 grams.
Now you can express the problem as a ratio and solve it....
19.3g/1cm^3 ~ 715g/Xcm^3. (a/b~c/d & solve for d)
Now solve: Multiply both sides by Xcm^3 which gives:
19.3g*Xcm^3/1cm^3 ~ 715g*Xcm^3/Xcm^3....
simplify to get:
19.3g*X =715g
divide each side by 19.3 to get
37.0466cm^3 which is the volume of gold with a mass of .715kg.
Take the cube root of this volume to get the length of a side of a cube of gold with this mass.

This gives you an edge length of approximately 3.402 cm.